FIG. 1 is a simplified block diagram of a conventional electronic funds and information transfer (EFIT) system 10 using a conventional centralized communications system 11 that allows a number of application programs 12 to communicate to outside devices 14 remotely located therefrom. For example, outside devices 13 may include one or more automated teller machines (ATMs) 14 and financial institutions 15 in an electronic funds and information transfer (EFIT) system coupled, through centralized communications system 11, to a router application program 16, a device handler program 17, and a funds transfer authorization program (AUTH) 18. Centralized communications system 11 may also be coupled to a journal program and database 19 for logging each transaction, and a host interface process 20 for interfacing with financial institutions 15.
In operation, when a transaction message for a cash withdrawal is generated at an ATM 14, for example, it goes to centralized communications system 11, which sends the transaction message to device handler 17. Device handler 17 then extracts information from the transaction message and builds a message having a predetermined internal format that is understood by application programs 12 and by centralized communications system 11. This reformatted message is then sent back to centralized communications system 11 which then forwards the message to router 16. Router 16 determines the destination for the message and sends the message back to centralized communications system 11 for delivery to the destination. The destination may be authorization program 18, which may access a database 21 to determine whether the transaction is authorized. The authorization contained in a return message is then sent to centralized communications system 11 for delivery to journal 19 to record the transaction, and then returned to device handler 17, again through centralized communications system 11. Device handler 17 then converts the authorization message into an external format and forwards it to the ATM from which the transaction originated through centralized communications system 11. ATM 14 then dispenses the funds requested or denies the transaction according to the information contained in the authorization message.
Where a transaction is required to obtain authorization from a financial institution 15, authorization program 18 would send the transaction message to interface program 20 through centralized communications system 11. Interface program 20 then reformats the message into one that is understood by the authorization system at financial institution 15, and sends the reformatted message to centralized communications system 11 for delivery to the destination financial institution for authorization. The financial institution then generates an authorization message and sends it to centralized communications system 11, which forwards it to interface program 20 for conversion back to the internal format understood by application programs 12 and centralized communications system 11. The reformatted authorization message is then sent to device handler 17 through centralized communications system 11, which then converts the message to the external format as described above to provide the authorization message to the ATM that originated the transaction.
It may be seen from the foregoing that all the messages communicated among application programs 12 and outside devices 13 must go through centralized communications system 11, which is the central controller. As the electronic funds and information transfer system becomes larger and larger to accommodate more and more ATMs and financial institutions, centralized communications system 11 becomes a bottleneck that slows down message delivery and transaction response time. This is a critical problem because transactions of this type typically require an almost instantaneous response time--banking customers do not like to wait more than thirty seconds for the ATM to respond to their cash withdrawal requests. Further, because all communications must go through centralized communications system 11, a single point, failure of system 11 would spell disaster for the entire electronic funds and information transfer system and disable all ATMs in the system.
Centralized communications system 11 has a further disadvantage of being required to recognize the message format in order to determine the destination of the message for routing purposes. Therefore, the message format cannot be easily changed without impacting the major functions of system 11.
The centralized architecture of the system also means that its growth is limited by the capacity of system 11. The system cannot be easily expanded to accommodate an order of magnitude more users without costly addition of computing platforms and other hardware components. In the computer industry, this feature of expandability is called "scalability." Further, a centralized system such as system 11 is not portable to other computing platforms, so that its deployment is restricted to a single platform.